The present invention relates to a new cleansing agent such as a shampoo. More particularly, this invention concerns a rinse-free shampoo which leaves less residue than conventional rinse-free shampoos and has a higher aqueous content.
Convention shampoos are made, primarily, of water, cleansing agents such as sodium dodecyl sulfate, thickeners, foam boosters, and fragrance. While these shampoos provide perfectly acceptable hair cleansing in most circumstances, they require a great deal of water to rinse the shampoo out of the hair. In most circumstances this is acceptable but rinsing is a serious problem for the infirm, e.g., geriatric patients and those otherwise hospitalized. While appearance is still an important factor to these people, they are often bedridden so they cannot easily use conventional means of washing their hair. Accordingly, "rinse-free" shampoos were developed several years ago. Rinse-free shampoos are used by rubbing into the hair, thereby entrapping or chelating the dirt particles and oils, and are removed by toweling and/or combing or brushing the hair. The term "rinse-free shampoo," as used herein, means a shampoo which requires little or no additional liquid for its operation.
Although the early rinse-free shampoos had some success, they has two major problems first, they did not clean hair as well as conventional shampoos; and second, they were apt to leave a large amount of residue on the hair. This residue, which may include chelated dirt, particulates from the shampoo itself, or other particulate forms, leaves the hair with a dull, unclean appearance, prevents the pleasing appearance sought by the consumer, and can lead to itchiness and scratching of the scalp. Further, the early shampoos washed away many of the natural oils.
The early rinse-free shampoos had sodium lauryl sulfate as their primary ingredient since the addition of ammonium ions gave problems with residue. Present rinse-free shampoos use materials such as triethanolamide lauryl sulfate, propylene glycol, and a small amount of cocamide diethanolamine. However, these formula modifications have not solved the problems caused by the residue, particularly the resultant greasy and/or gritty feeling of the hair.
Accordingly, an object of the invention is to provide a rinse-free shampoo which is inexpensive yet solves the problems of residue build-up and provides a clean, shiny appearance to the hair.
A further object of the invention is to provide a biodegradable rinse-free shampoo which can be used for camping or other purposes where a conventional shampoo is not convenient.
A further object of the invention is to provide a shampoo for geriatric and other infirm patients.
These and other objects and features of the invention will be apparent from the following description.